Hi, I'm writing a LabVIEW application using the Actor Framework. This is the first time that I have used the framework and I need some advice regarding application architecture. My apologies if this is a basic question!
How is a settings dialog box best implemented? In the past in non-Actor Framework applications I have loaded the configuration from a functional global variable, displayed the settings dialog, then written the updated settings back to the functional global. I'm not sure this would work correctly (or optimally) within the context of the Actor Framework, though.
My application uses the template generated by Create Project -> Actor Framework. The top-level Actor manages the user interface. Two child Actors control separate pieces of hardware. The top-level actor must read a saved configuration from an INI file when the application starts, and save the final configuration back to the INI file on exit.
Instinctively I think it would be best for each child actor to maintain its own settings, as a cluster in its class private data. Ideally I don't want to have to keep a separate instance of the two clusters of settings in the top-level Actor's private data in order to populate a settings dialog; this duplication seems unnecessary.
The only way I can think of to make this work is as follows.
At application start
1. Top-level Actor reads settings from INI file.
2. Send messages to both child actors with the new settings, and tell them to apply those settings to their private data.
3. Each child Actor should respond to acknowledge that the private data has been updated.
To update the settings using a dialog box
1. Send a message from the top-level Actor to each child Actor to ask them to send their settings to the top-level Actor.
2. Wait for both child Actors to reply.
3. Display the dialog box.
4. If the user clicked 'Ok' and not 'Cancel', send messages to both actors with the new settings, and tell them to apply those settings to their private data.
5. Each child Actor should respond to acknowledge that the private data has been updated.
On exit
1. Send a message from the top-level Actor to each child Actor to ask them to send their settings to the top-level Actor.
2. Wait for both child Actors to reply.
3. The top-level Actor writes the settings to the INI file.
This doesn't seem like a sensible approach, though. Waiting for message replies sounds like the wrong thing to do. I wouldn't know where in the block diagram to implement this scheme, either.
Can anyone offer me any advice? There must be a fairly standard way of doing this that I'm missing!
Thanks in advance,
Chris
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Dr. Chris Empson
Robot Screening and Instrumentation Specialist
School of Chemistry
University of Leeds
UK
CLD
